In the polymerization of vinyl chloride, whether it is by a batch or continuous method, generally there is some unreacted vinyl chloride monomer. This unreacted monomer normally has been vented from the product or stripped from the product in a stripping operation and then discharged as a vent gas stream to the atmosphere. Although this process was clearly acceptable in the early days of polyvinyl chloride production, this method has now come under attack. Recently investigators have found that vinyl chloride, when inhaled, may be carcinogenic and in order to prevent the possibility of harm to people, environmental standards have been issued by the government. These standards now require that the concentration of vinyl chloride, as monomer, in a gas stream which is to be discharged to the atmosphere be less than about 20 parts per million, and preferably less than about 10 parts per million.